Typically, two kinds of IC storage magazines are used for an IC test handler, i.e. a tray type magazine and rod-shaped magazine. IC handler systems have been designed specifically for either one of the two types of storage magazines.
Examples of an IC transfer apparatus with the tray type magazine and rod-shaped magazine of the prior art are explained with reference to FIGS. 3 and 4.
First, the transfer section of an IC transfer system using the tray type magazine includes a user tray 170, a tray supply section 172, a supply tray 172, a supply tray transfer mechanism 174, a tray conversion section 173, a tray conversion transfer mechanism 175, a test tray 180, a test section 182, a sorting buffer stand 184, a storage tray transfer mechanism 186, and a tray storage section 189. The above-mentioned components for the transfer section are briefly described below.
The user tray 170 is a disc-shaped container and has an array of many depressed pockets for storing devices in the lateral and longitudinal directions. The devices are stored in these pockets. Multiple user trays 170 are stored in many layers in the tray supply section 172.
The supply tray transfer mechanism 174 lifts the user tray 170 from the upper most stage of the many layered user trays 170 using at transfer arm. The transfer mechanism then transfers the tray 170 and places the user tray 170 on the tray conversion section 173.
The tray conversion transfer mechanism 175 transfers the device from the user tray 170 placed on the tray conversion section 173 to the test tray 180. Typically, the transfer mechanism 175 lifts, by suction, one or more of the IC devices and transfers to the IC devices to the test tray 180 using the suction section 175a. Thereafter, the IC device is placed at a predetermined test spot on the test tray 180. Performing this step multiple times completes the transfer of all of the IC devices.
The test tray 180 that stores the devices is transferred to the test section 182 where the device is heated/cooled to the preset temperatures, then electrical tests are conducted and the device stored in the test tray 180 is ejected to the sorting buffer stand 184.
The storage tray transfer mechanism 186 lifts the device on the test tray 180 (which is located in the sorting buffer stand 184) with a suction section 186a, and transfers the device over to the position of the user tray 170. Within the user tray 170, the IC devices are sorted into groups determined by the test results. The device is thereby stored in the tray 170.
The tray storage section 189 arranges multiple user trays 170 according to the test result criterion, and stores the IC devices deposited by the storage transfer mechanism 186. Repeating the above mentioned operation executes the supply and sorting/storage of all of the IC devices within the user tray 170.
Second, the transfer section of an IC transfer apparatus having a rod type storage magazine is illustrated in FIG. 4. As shown in FIG. 4, the IC transfer apparatus includes a magazine 150, a magazine supply section 152, a supply magazine transfer mechanism 154, a test section 156, a storage magazine transfer mechanism 158, and a magazine storage section 160. The type of IC handler depicted in FIG. 4 is a selfweight fall system which relies on gravity to slide and drop the IC device during the transfer stages. The following description is a summary of the transfer operation.
The magazine 150 is a rod-shaped container that stores ICs in one row and adopts different configurations depending on the size and shape (DIP, ZIP, SOP) of the ICs. A plurality of the magazines 150 are stored in the magazine supply section 152.
The supply magazine transfer mechanism 154 tilts a magazine 150a by supporting one end of a magazine 150 from the magazine supply section 152, and lifting the other end of the magazine 150 to rotate the magazine 150. The IC devices are separated one by one by their own weight due to the inclined angle from an I rail section 155a and stored in an ER rail 155b.
The ER rail 155b is arranged in a row so as to store multiple IC devices, and the ER rail 155b stores the IC devices one by one from the previously mentioned I rail 155a by moving the ER rail 155b laterally. Thereafter, the ER rail 155b is moved laterally and positioned so as to match with a S rail 155c in multiple rows. The IC devices slide into to the S rail 155c.
The S rail 155c moves the IC devices on the S rail 155c one by one by sliding, and supplies the IC devices to the test section 156 side. In addition, the S rail 155c functions as a buffer for heating/cooling the devices to a constant temperature if desired.
The test section 156 receives the devices from the S rail 155c and performs electrical tests such as fault/no fault inspections and characteristic measurements, etc. by electrical contact with the devices. Thereafter, the IC devices are ejected to the store magazine transfer mechanism 158 side.
The storage magazine transfer mechanism 158 receives the devices from the test section 156, and sorts them by the inspection results of the fault/no fault and characteristics tests. Thus, the IC devices are stored in the magazine 150b based upon test result classifications of the storage magazines 150n which are arranged in multiple rows. For this operation, a sorter 159 receives the devices and moves laterally to the corresponding magazine 150n arranged in a row. The IC devices are deposited in the appropriate magazine by sliding into the storage magazines 150b which are inclined.
The magazine storage section 160 holds the magazines 150n which are arranged in multiple rows and stores the IC devices by sorting corresponding to the previously mentioned inspection results. Repeating the above mentioned operation accomplishes the supply and sorting/storage of IC devices by the magazine 150.
As explained thus far, in the case of the tray type magazine, the structure of these devices is such that ICs are transferred horizontally by holding and releasing the ICs by suction. On the contrary, in the case of the rod-shaped magazine, the structure of the transfer apparatus is such that IC devices are dropped by their own weight by tilting the magazine. Therefore, both the IC transfer mechanisms differ significantly. This makes it difficult for an IC handler to provide the appropriate transfer operations in conjunction with both kinds of magazine configurations.
Recently, there has been an increase in the number of device types and configurations tested by the IC handler. For example, there are devices having identical logic but different configurations; or an IC handler might need to flexibly adapt container configurations on the supply side and the storage side; furthermore, it may be desirable to transport the ICs with either the rod-shaped magazine or tray type magazine.
However, as mentioned above, it would not be desirable to have an IC handler with a fixed one magazine configuration because this would limit the kinds of IC supply and storage containers which could be used in conjunction with the IC handler. In addition, such an IC handler with a fixed one magazine configuration is impractical since its configuration poses practical limitations in utilizing the IC handler.
Furthermore, generally speaking, in testing semiconductor ICs, a handler together with the IC tester transfers and handles a tray where an IC to be measured (called a device under test, or "DUT") is placed. The handler also loads, tests, and finally, sorts by the classifications based on the test results and unloads.
The following briefly explains an exemplary transfer path of a magazine loader section 242, the test tray 180, and a DUT 215, as well as the testing method in a handler 221 having a temperature chamber 235. As shown in FIG. 6, the DUT 215 that is stored in the magazine in the magazine loader section 242 inside the handler 221 is transferred and replaced on another test tray 180 that can withstand high/low temperatures through a precision carrier 240. After the test tray 180 is transferred and circulated along a preset path, the DUT 215 is tested in a test area 237. That is, the electrical characteristics of the DUT 215 are measured under a constant temperature in the test area 237 after it is brought inside the constant temperature chamber 235, heated or cooled in a soak chamber 236 and reaches a constant temperature. Thereafter, the DUT is returned to the external temperature in a EXIT chamber 238.
The DUT 215 that is tested at low/high temperatures and returned to the external temperature in the EXIT chamber 238 is sent to an unloader section 223 while remaining on the test tray 180. The DUT 215 is then moved from the test tray 180 to a customer tray 216 or moved from the test tray 180 to a magazine unloader section 243 through a sorting carrier 241 and sorted by classifications based on the test results and transferred/stored. A suction transfer means using a vacuum pump is arranged for transferring the DUT 215 between the test tray 180 and customer tray 216, and one or more of the DUT 215 are sucked, held and transferred to another tray, and the transfer from one place to another is completed by releasing the DUT 215.
A further example of transferring the customer tray 216 from one tray storage section 225 to another tray storage section 225 is explained with reference to FIG. 7. The loader section 222, unloader section 223 and empty tray storage section 224 have multiple lanes, for example 10 lanes, which are composed of the tray storage section 225 and an elevator 226 that moves the customer tray 216 stored in the tray storage section 225 up to a level of position C as indicated by 1. In the tray storage section 225 of the loader section 222, the customer trays 216 where the DUT 215 is placed, are stacked together. All the lanes are identical and there is no distinction among the loader lanes, unloader lanes, and empty tray storage lanes. Thus, the multiple lanes (e.g., 10 lanes) are arranged in a simple layout. These lanes are designated as the loader lanes, unloader lanes, or empty tray storage lanes as required.
For example, as shown in FIG. 7, lane 1 is designed as the loader section 222 that loads the DUT 215 to be tested, lanes 2 through 9 are designated as the unloader section 223 that stores the DUT 215, (i.e., those which are already tested), by categories based on the test results. Lane 10 is designated as the empty tray storage section 224 that stores the customer trays 216 that are finished loading. The number of lanes designated to each function changes in accordance with the particular system requirements. A tray transfer system 227 transfers the customer tray 216 by hooking the tray 216 using hooks 228. Mating holes 229 on the customer tray 216 are arranged to engage with the hooks 228 of the tray transfer system 227.
FIG. 8 illustrates the process by which the tray transfer system 227 separates and transfers the upper most tray from the multiple layered customer trays 216 inside the tray storage section 225. The tray transfer system 227 is driven to a level of position C or position B by a drive mechanism as shown in FIG. 7. The transfer system 227 is driven horizontally at the level of position B over the lanes 1 through 10 arranged horizontally as indicated by 3. A tray set 230 which receives and handles the transferred DUT 215 between the customer tray 216 and test tray 180. The tray set 230 is driven to the level of position C or position A by the drive system as indicated by 4.
Here, the process by which the DUT 215 to be tested is transferred and placed onto the test tray 180 is explained below with reference to FIG. 7.
(1) raise the upper most customer tray 216 to position C by pushing the layered customer trays 216 on the tray storage section 225 in the lane 1 using the elevator 226. PA1 (2) position the tray transfer system 227 directly above the lane 1 by horizontally driving at the level of position B. PA1 (3) move the tray transfer system 227 down to the level of position C. PA1 (4) hook the upper most customer tray 216 in the lane 1 by controlling the hook 226 of the tray transfer system 227. PA1 (5) raise the tray transfer system 227 that hooked the upper most customer tray 216 from position C to position B. PA1 (6) move the tray transfer system 227 that hooked the customer tray 216 raised to the level of position B to the lane 3 at the level of position B. PA1 (7) fix the tray set 230 at the level of position C in the loader section 222. PA1 (8) move the tray transfer system 227 positioned at position B in the lane 3 to the upper section of the loader 222. PA1 (9) release and hand over the hooked customer tray 216 over the tray set 230 of the loader section 222 by controlling the hooks 228 of the tray transfer system 227. PA1 (10) move the tray transfer system 227 that released the hooked customer tray 216 to the lane 3 by driving horizontally. PA1 (11) raise the tray set 230 of the loader section 222 which received the customer tray 216 from the level of position C to the level of position A, and complete the setup of the customer tray 216 to the tray set 230 in the loader section 222.
Next, the DUT 215 placed on the customer tray 216 is transferred and placed on the test tray 180 inside the handler 221 (which can withstand high/low temperatures) by a suction transfer device using a vacuum pump. The test tray 180 where the DUT 215 is placed, is moved into the temperature chamber 235 and the tests are conducted.
The test tray 180 where the tested DUT 215 is placed, is moved out from the temperature chamber 235 to the unloader section 223. In the unloader section 223, in accordance with the procedure of transferring from the previously mentioned customer tray 216 to the test tray 180, the test tray 180 is transferred and placed on the customer tray 216. At this juncture, the DUT 215 is sorted into 2 to 8 categories based on the test results of the DUT 215. These classifications can be set arbitrarily based on the test objectives of each IC manufacturer.
If an IC manufacturer only wishes to test for a defect or no defect, then only two classifications are necessary. However, most IC manufacturers want the ICs to be tested for multiple characteristics so that the ICs are typically classified into more than 4 categories. For example, for the performance specification of the DUT 215, products with the best test data are classified with category 0, and good products are placed in category 1, products barely satisfying the specification are placed in category 2, and defects are placed in category 3. The categories 0 and 1 are considered good products unconditionally whereas the categories 2 and 3 are considered either a defect or a device which needs reinspection. In the case where 8 categories or classifications are used, the performance specification is divided into 8 categories. Hence, the sorting process takes longer time.
The transfer of the DUT 215 from the magazine of the magazine loader section 242 to the test tray 180 is explained with reference to FIG. 6. The DUT 215 are stored in series inside the magazine, and they are loaded into the precision carrier 240 a few pieces at a time by tilting the magazine and letting them fall by their own weight. The precision carrier 240 can be moved horizontally and moved proximate to the test tray 180. The DUT 215 loaded into the precision carrier 240 is transferred to the test tray 180 by a suction transfer device using a vacuum pump.
In addition, the transfer of the DUT 215 from the test tray 180 to the magazine unloader section 243 is explained. Here, the sort carrier 241 can be moved horizontally, and moved near the test tray 180. The DUT 215 loaded on the test tray 180 is transferred to the sort carrier 241 by the suction transfer device using a vacuum pump. The sort carrier 241 moves to the magazine loader section 242, and the DUT 215 is dropped by gravity in the tilted magazine arranged inside the magazine loader section and stored in series in the magazine.
As mentioned above, the IC tests using the IC test handler can be performed automatically during high/cold temperatures by setting the magazine holding a number of ICs to the magazine loader section 242, and they are sorted based on the predetermined setting upon the completion of the tests. Hence, the IC test handler is very convenient. However, because the IC test handles are expensive, it is essential that the IC test handlers shorten the test time and improve efficiency by eliminating human intervention.